paintarea.h Example File
tools/plugandpaint/paintarea.h
    /****************************************************************************
    **
    ** Copyright (C) 2005-2006 Trolltech AS. All rights reserved.
    **
    ** This file is part of the documentation of the Qt Toolkit.
    **
    ** This file may be used under the terms of the GNU General Public
    ** License version 2.0 as published by the Free Software Foundation
    ** and appearing in the file LICENSE.GPL included in the packaging of
    ** this file.  Please review the following information to ensure GNU
    ** General Public Licensing requirements will be met:
    ** http://www.trolltech.com/products/qt/opensource.html
    **
    ** If you are unsure which license is appropriate for your use, please
    ** review the following information:
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    **
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    ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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    ****************************************************************************/
    #ifndef PAINTAREA_H
    #define PAINTAREA_H
    #include <QColor>
    #include <QImage>
    #include <QPainterPath>
    #include <QWidget>
    class BrushInterface;
    class PaintArea : public QWidget
    {
        Q_OBJECT
    public:
        PaintArea(QWidget *parent = 0);
        bool openImage(const QString &fileName);
        bool saveImage(const QString &fileName, const char *fileFormat);
        void setImage(const QImage &image);
        void insertShape(const QPainterPath &path);
        void setBrushColor(const QColor &color);
        void setBrushWidth(int width);
        void setBrush(BrushInterface *brushInterface, const QString &brush);
        QImage image() const { return theImage; }
        QColor brushColor() const { return color; }
        int brushWidth() const { return thickness; }
        QSize sizeHint() const;
    protected:
        void paintEvent(QPaintEvent *event);
        void mousePressEvent(QMouseEvent *event);
        void mouseMoveEvent(QMouseEvent *event);
        void mouseReleaseEvent(QMouseEvent *event);
    private:
        void setupPainter(QPainter &painter);
        QImage theImage;
        QColor color;
        int thickness;
        BrushInterface *brushInterface;
        QString brush;
        QPoint lastPos;
        QPainterPath pendingPath;
    };
    #endif